Officials: South Fla. water table rose up to three inches after quake

March 20, 2011

WEST PALM BEACH, Fla. (AP) — The devastating earthquake that shook Japan caused a temporary jolt in groundwater levels throughout much of Florida, officials said.

The South Florida Water Management District reports that a network of groundwater gauges registered a jump of up to three inches in the water table from Orlando to the Florida Keys about 34 minutes after the quake struck on March 11.

The oscillations were observed for about two hours and then stabilized.

"We were not expecting to see any indication of the geological events in Japan given the island's great distance from Florida," Susan Sylvester, the water district's director of operations control and hydro data management department, said on Saturday.

Shimon Wdowinski, an earthquake researcher with the University of Miami, said the water table likely rose because of Florida's porous limestone, which allows water to easily flow beneath the earth's surface and respond to changes in pressure caused by a wave.

He said the flow of Florida's aquifer is quite fast.

"It's good because we can filter a lot of water through there," Wdowinski said. "But it's bad because in the case of pollution, it can travel very quickly."

Changes in groundwater levels were also seen in South Florida after the Haiti and Chile earthquakes. Wdowinski said a 20-foot rise was seen after a 9.2 earthquake in Alaska in 1964.

"I wouldn't say it's normal, but it's not unusual," Wdowinski said of the variations.

The water district says the data was collected from a series of wells with recording devices. Randy Smith, a spokesman for the water district, said the reverberations were observed hundreds of feet below the surface. He and others expressed surprise at the events, given the distance from Japan.

"This was over 7,000 miles," he said. "I think that proves how strong the earthquake was."